1. Field of the Invention
The invention relates to a swaging hold method, a swaging hold structure, a swaging roller, a swaging machine, and a swaging hold work, which are used to form a swaged portion by bending an end portion of a workpiece by swaging to hold a held member along a base portion of the workpiece by a holding force exerted by the swaged portion.
2. Description of the Related Art
A rotation/linear motion converting actuator is available, of which the subject apparatus to be driven is an internal combustion engine, for example, and that is installed on the apparatus to provide a linear driving force to the subject apparatus (see Japanese Patent Application Publication No. 2007-303408 (JP-A-2007-303408), Japanese Patent Application Publication No. 2007-303479 (JP-A-2007-303479)). JP-A-2007-303408 and JP-A-2007-303479 describe the rotation/linear motion converting actuator that drives the valve lift mechanism for an internal combustion engine. A rotary shaft is rotatably supported, via a bearing, in a body case of the rotation/linear motion converting actuator. The rotary shaft is driven to rotate by a motor, which causes a screw shaft to linearly move in the axial direction, thereby driving the valve lift mechanism.
In JP-A-2007-303408 and JP-A-2007-303479, in order to fix the bearing for rotatably supporting the rotary shaft in a housing, an annular supporting member is disposed in the housing and the supporting member is fastened to the inner surface of the housing with bolts.
Due to the construction in which the annular supporting member to fix the bearing is disposed in the housing and fastened with bolts in this way, the size of the housing tends to become large. It is conceivable to use a swaging process (see Japanese Patent Application Publication No. 2001-50291 (JP-A-2001-50291), Japanese Patent Application Publication No. 2000-6610 (JP-A-2000-6610), and Japanese Patent Application Publication No. 2002-21867 (JP-A-2002-21867)) in combination to support the bearing.
However, when a held member, such as a bearing, that requires a certain level of holding force is held by the housing, if the held member is held by merely swaging the housing, there is a fear that the holding force for holding the held member is insufficient. Specifically, when it is tried to strengthen the holding force exerted by the swaged portion of the housing by increasing the pressure applied when the swaging is performed, most of the amount of increase in pressure contributes to the increase in the plastic deformation in the radial direction that is orthogonal to the axial direction at the swaged portion. Thus, there has been a problem that it is impossible to sufficiently increase the axial residual stress in the housing that should produce the holding force finally.